Pigeon pea crop stage strongly influences plant susceptibility to Helicoverpa armigera (Lepidoptera: Noctuidae).

Helicoverpa armigera Hübner (Lepidoptera: Noctuidae; Hübner) is the major insect pest of pigeon pea [Cajanus cajan; Fabales: Fabaceae; (L.) Millspaugh] worldwide. Research to develop pest management strategies for H. armigera in pigeon pea has focused heavily on developing less susceptible cultivars, with limited practical success. We examined how pigeon pea crop stage influences plant susceptibility to H. armigera using a combination of glasshouse and laboratory experiments. Plant phenology significantly affected oviposition with moths laying more eggs on flowering and podding plants but only a few on vegetative plants. Larval survival was greatest on flowering and vegetative plants, wherein larvae mostly chose to feed inside flowers on flowering plants and on the adaxial surface of expanding leaves on vegetative plants. Larval survival was poor on podding plants despite moths laying many eggs on plants of this stage. When left to feed without restriction on plants for 7 days, larvae feeding on flowering plants were >10 times the weight of larvae feeding on plants of other phenological stages. On whole plants, unrestricted larvae preferred to feed on pigeon pea flowers and on expanding leaves, but in no-choice Petri dish assays H. armigera larvae could feed and survive on all pigeon pea reproductive structures. Our results show that crop stage and the availability of flowers strongly influence pigeon pea susceptibility to H. armigera. An increased understanding of H. armigera-pigeon pea ecology will be useful in guiding the development of resistant varieties and other management tactics.

What Defines a Host? Oviposition Behavior and Larval Performance of Spodoptera frugiperda (Lepidoptera: Noctuidae) on Five Putative Host Plants.

When an invasive species first breaches quarantine and establishes in yet another country, it invariably causes consternation for growers, in part because of incomplete understanding of the plants that are at risk. The Fall Armyworm, Spodoptera frugiperda (J.E. Smith) is the most recent example in Australia. The number of plants that this polyphagous noctuid is reported to attack is vast, including many crop species. Consequently, initial reactions from grower industry groups that perceived themselves at risk were to demand emergency use of insecticides. Yet the field evidence suggests that many crops might not be at risk and since S. frugiperda arrived in Australia, maize crops have suffered most damage, followed by sorghum. We question the accuracy of some of the claims of reported host plants of S. frugiperda and report experiments that compared oviposition behavior, neonate silking behavior, and larval performance on five crops: the known hosts maize and sorghum, and the putative hosts cotton, peanut, and pigeon pea. Maize ranked highest in all preference and performance measures, followed by sorghum and peanut, with pigeon pea and cotton ranking lowest. Although S. frugiperda can survive, develop, and pupate on the crop species we examined, cotton and pigeon pea are not preferred by the pest in either the larval or adult stages. We suggest that before a plant is listed as a host for a given insect that the evidence should be fully reported and carefully evaluated. Collecting an immature insect from a plant does not make that plant a host!

Balancing nutrients in a toxic environment: the challenge of eating.

Insect herbivores can regulate their food intake by mixing food sources with different nutrient content, but face the resulting challenge of ingesting various plant secondary metabolites. How insects deal with toxins in a complex nutrient environment is unclear. Here we investigated the influence of a classic plant secondary metabolite, allyl glucosinolate (sinigrin), and its hydrolyzed product allyl isothiocyanate (AITC), on the development of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) when fed on diets with different protein-to-carbohydrate (p : c) ratios. We also examined the effects of these toxins on larval biochemistry, by chemically analyzing the frass produced by insects feeding on the different diets. As expected, AITC had a greater negative effect than sinigrin on H. armigera life-history traits. However, AITC at low concentration appeared to have a positive effect on some traits. Both sinigrin and AITC-induced detoxification activity in the gut, and the reaction was related to diet protein concentration. High-protein diets can provide the required free amino acid, especially cysteine, needed for the detoxification process. The nutrient content of the diet influences how plant secondary metabolites are handled, and the use of artificial diets in experiments investigating the metabolic fate of plant secondary compounds needs to be carefully evaluated.

Australian sugarcane soldier fly's salivary gland transcriptome in response to starvation and feeding on sugarcane crops.

The soldier fly is an endemic pest of sugarcane in Australia. Small numbers of larvae can cause significant damage to roots and reduce the crop yields. Little is known about the composition and function of the soldier fly salivary gland, its secretions, and their roles in insect-plant interactions. In this study, we performed transcriptome analysis of the salivary glands of starved and sugarcane root-fed soldier fly larvae. A total of 31 119 highly expressed assembled contigs were identified in the salivary glands and almost 50% of them showed high levels of similarity to known proteins in Nr databases. Of all the obtained contigs, only 9727 sequences contain an open reading frame of over 100 amino acids. Around 31% of contigs were predicted to encode secretory proteins, including some digestive and detoxifying enzymes and potential effectors. Some known salivary secreted peptides such as serine protease, cysteine proteinase inhibitors, antimicrobial peptides and venom proteins were among the top 100 highly expressed genes. Differential gene expression analysis revealed significant modulation of 850 transcripts in salivary glands upon exposure to plant roots or starvation stress. Here, we identified some venom proteins which were significantly upregulated in the salivary glands of soldier fly larvae exposed to sugarcane roots. In other insects and nematodes some of these proteins have been used to manipulate host plant defense systems and facilitate the invasion of the host plant. These findings provide a further insight into the identification of potential effector proteins involved in soldier fly-sugarcane interactions.

Spatial and Temporal Dynamics of the Native Banana-Spotting Bug, Amblypelta lutescens lutescens (Hemiptera: Coreidae), in Avocado Crops in North Queensland, Australia.

The native banana-spotting bug, Amblypelta lutescens lutescens Distant, is a major polyphagous insect pest of many tropical and subtropical horticultural crops in Australia, including high-valued commodities such as avocado (Persea americana Mill. (Laurales: lauraceae)). The cryptic nature of A. l. lutescens makes it difficult to sample, and much about its ecology and behavior remains poorly understood. A lure based on the main components of the semiochemicals emitted by male A. l. lutescens, which is attractive to adult males, adult females, and nymphs, has been developed and incorporated into a trap, facilitating sampling of A. l. lutescens in the field. A 2-yr study investigated the spatial and temporal dynamics of the pest in two conventionally managed avocado (cv. Shepard) orchards using a grid (36 m × 36 m) of traps across each. In each year of the study, higher numbers of A. l. lutescens were recorded from October to June. In one field, spatial clustering of adults was detected in close proximity to an adjacent lime [Citrus aurantiifolia (Christm.) (Rutales: rutaceae) Swingle] crop that was not managed with insecticides during the study. Spatial clustering of nymphs was detected adjacent to native riparian vegetation in the other field. The results suggest that source populations of A. l. lutescens could originate from neighboring crops that host A. l. lutescens and from riparian vegetation. Focused sampling of trees at the interface with these vegetation types could lead to early pest detection, timely suppression, and therefore improved pest management.

Effects of mischievous responding on universal mental health screening: I love rum raisin ice cream, really I do!

Student surveys are often used for school-based mental health screening; hence, it is critical to evaluate the authenticity of information obtained via the self-report format. The objective of this study was to examine the possible effects of mischievous response patterns on school-based screening results. The present study included 1,857 high school students who completed a schoolwide screening for complete mental health. Student responses were reviewed to detect possible mischievous responses and to examine their association with other survey results. Consistent with previous research, mischievous responding was evaluated by items that are legitimate to ask of all students (e.g., How much do you weigh? and How many siblings do you have?). Responses were considered "mischievous" when a student selected multiple extreme, unusual (less than 5% incidence) response options, such as weighing more than 225 pounds and having 10 or more siblings. Only 1.8% of the students responded in extreme ways to 2 or more of 7 mischievous response items. When compared with other students, the mischievous responders were less likely to declare that they answered items honestly, were more likely to finish the survey in less than 10 min, reported lower levels of life satisfaction and school connectedness, and reported higher levels of emotional and behavioral distress. When applying a dual-factor mental health screening framework to the responses, mischievous responders were less likely to be categorized as having complete mental health. Implications for school-based mental health screening are discussed. (PsycINFO Database Record

Diclofenac and Its Acyl Glucuronide: Determination of In Vivo Exposure in Human Subjects and Characterization as Human Drug Transporter Substrates In Vitro.

Although the metabolism and disposition of diclofenac (DF) has been studied extensively, information regarding the plasma levels of its acyl-ß-d-glucuronide (DF-AG), a major metabolite, in human subjects is limited. Therefore, DF-AG concentrations were determined in plasma (acidified blood derived) of six healthy volunteers following a single oral DF dose (50 mg). Levels of DF-AG in plasma were high, as reflected by a DF-AG/DF ratio of 0.62 ± 0.21 (Cmax mean ± S.D.) and 0.84 ± 0.21 (area under the concentration-time curve mean ± S.D.). Both DF and DF-AG were also studied as substrates of different human drug transporters in vitro. DF was identified as a substrate of organic anion transporter (OAT) 2 only (Km = 46.8 µM). In contrast, DF-AG was identified as a substrate of numerous OATs (Km = 8.6, 60.2, 103.9, and 112 µM for OAT2, OAT1, OAT4, and OAT3, respectively), two organic anion-transporting polypeptides (OATP1B1, Km = 34 µM; OATP2B1, Km = 105 µM), breast cancer resistance protein (Km = 152 µM), and two multidrug resistance proteins (MRP2, Km = 145 µM; MRP3, Km = 196 µM). It is concluded that the disposition of DF-AG, once formed, can be mediated by various candidate transporters known to be expressed in the kidney (basolateral, OAT1, OAT2, and OAT3; apical, MRP2, BCRP, and OAT4) and liver (canalicular, MRP2 and BCRP; basolateral, OATP1B1, OATP2B1, OAT2, and MRP3). DF-AG is unstable in plasma and undergoes conversion to parent DF. Therefore, caution is warranted when assessing renal and hepatic transporter-mediated drug-drug interactions with DF and DF-AG.

Genome wide discovery of long intergenic non-coding RNAs in Diamondback moth (Plutella xylostella) and their expression in insecticide resistant strains.

Long non-coding RNAs (lncRNAs) play important roles in genomic imprinting, cancer, differentiation and regulation of gene expression. Here, we identified 3844 long intergenic ncRNAs (lincRNA) in Plutella xylostella, which is a notorious pest of cruciferous plants that has developed field resistance to all classes of insecticides, including Bacillus thuringiensis (Bt) endotoxins. Further, we found that some of those lincRNAs may potentially serve as precursors for the production of small ncRNAs. We found 280 and 350 lincRNAs that are differentially expressed in Chlorpyrifos and Fipronil resistant larvae. A survey on P. xylostella midgut transcriptome data from Bt-resistant populations revealed 59 altered lincRNA in two resistant strains compared with the susceptible population. We validated the transcript levels of a number of putative lincRNAs in deltamethrin-resistant larvae that were exposed to deltamethrin, which indicated that this group of lincRNAs might be involved in the response to xenobiotics in this insect. To functionally characterize DBM lincRNAs, gene ontology (GO) enrichment of their associated protein-coding genes was extracted and showed over representation of protein, DNA and RNA binding GO terms. The data presented here will facilitate future studies to unravel the function of lincRNAs in insecticide resistance or the response to xenobiotics of eukaryotic cells.

Dimer of arfaptin 2 regulates NF-κB signaling by interacting with IKKß/NEMO and inhibiting IKKß kinase activity.

IκB kinases (IKKs) are a therapeutic target due to their crucial roles in various biological processes, including the immune response, the stress response, and tumor development. IKKs integrate various upstream signals that activate NF-κB by phosphorylating IκB and also regulate many proteins related to cell growth and metabolism. Although they function as a heteromeric complex comprised of kinase subunits and an adaptor, these kinases produce distinct cellular responses by phosphorylating different target molecules, suggesting that they may also be regulated in a subtype-specific manner. In this study, arfaptin 2 was identified as an IKKß-specific binding partner. Interestingly, arfaptin 2 also interacted with NEMO. Domain mapping studies revealed that the C-terminal region, including the IKKß HLH domain and the first coiled-coil NEMO region were respectively required for interactions with the arfaptin 2 N-terminal flexible region. Overexpression of arfaptin 2 inhibited tumor necrosis factor (TNF)-α-stimulated nuclear factor-κB (NF-κB) signaling, whereas downregulation of arfaptin 2 by small interfering RNA enhanced NF-κB activity. Dimerization of arfaptin 2 through the Bin-Amphiphysin-Rvs domain may be essential to inhibit activation of NF-κB through multimodal interactions with IKKßs or IKKß/NEMO, as ectopic expression of the arfaptin 2 fragment responsible for IKK interactions did not change TNFα-stimulated NF-κB activation. These data indicate that arfaptin 2 is the first molecule to regulate NF-κB signaling by interacting with the functional IKK complex but not by direct inhibiting IKKß phosphorylation.

An exploratory universal LC-MS/MS assay for bioanalysis of hinge region-stabilized human IgG4 mAbs in clinical studies.

BACKGROUND: Due to the increasing number of monoclonal antibody (mAb) drug candidates entering clinical development, bioanalytical laboratories can benefit from generic liquid chromatography-tandem mass spectrometry (LC-MS/MS) assays capable of quantifying a variety of human mAb-based therapeutic drug candidates in plasma/serum samples from clinical studies. RESULTS: We have developed and evaluated an exploratory LC-MS/MS assay capable of quantifying hinge region-stabilized IgG4 therapeutic mAb drugs and drug candidates in clinical samples. The exploratory assay is based upon a single 'universal IgG4' surrogate peptide. CONCLUSION: The novel exploratory LC-MS/MS assay reported herein, upon further refinement and full validation, is predicted to enable bioanalytical scientists to quantify all hinge region-stabilized human IgG4 therapeutic mAbs in human studies without having to develop a new assay for every new stabilized IgG4 mAb entering clinical development.

Mcl1 regulates the terminal mitosis of neural precursor cells in the mammalian brain through p27Kip1.

Cortical development requires the precise timing of neural precursor cell (NPC) terminal mitosis. Although cell cycle proteins regulate terminal mitosis, the factors that influence the cell cycle machinery are incompletely understood. Here we show in mice that myeloid cell leukemia 1 (Mcl1), an anti-apoptotic Bcl-2 protein required for the survival of NPCs, also regulates their terminal differentiation through the cell cycle regulator p27(Kip1). A BrdU-Ki67 cell profiling assay revealed that in utero electroporation of Mcl1 into NPCs in the embryonic neocortex increased NPC cell cycle exit (the leaving fraction). This was further supported by a decrease in proliferating NPCs (Pax6(+) radial glial cells and Tbr2(+) neural progenitors) and an increase in differentiating cells (Dcx(+) neuroblasts and Tbr1(+) neurons). Similarly, BrdU birth dating demonstrated that Mcl1 promotes premature NPC terminal mitosis giving rise to neurons of the deeper cortical layers, confirming their earlier birthdate. Changes in Mcl1 expression within NPCs caused concomitant changes in the levels of p27(Kip1) protein, a key regulator of NPC differentiation. Furthermore, in the absence of p27(Kip1), Mcl1 failed to induce NPC cell cycle exit, demonstrating that p27(Kip1) is required for Mcl1-mediated NPC terminal mitosis. In summary, we have identified a novel physiological role for anti-apoptotic Mcl1 in regulating NPC terminal differentiation.

Dual universal peptide approach to bioanalysis of human monoclonal antibody protein drug candidates in animal studies.

BACKGROUND: There is a need for general and reliable LC-MS assays capable of supporting the bioanalysis of a variety of human monoclonal antibody-based therapeutic drug candidates in animal PK/TK studies. RESULTS: We present herein improvements in our previously reported universal peptide approach to the bioanalysis of human monoclonal antibody protein drug candidates in animal studies. These improvements include incorporation of a second, light chain-based universal peptide into the assay, thus introducing the concept of a dual universal peptide assay; and incorporation of a universal stable isotope-labeled monoclonal antibody into the assay. CONCLUSION: Improvements reported herein to the universal peptide assay will enable more reliable quantification of human monoclonal antibody protein drug candidates in animal studies.

Adjuvant whole brain radiation following resection of brain metastases.

Brain metastasis is a common complication of systemic cancer and significant cause of suffering in oncology patients. Despite a plethora of available treatment modalities, the prognosis is poor with a median survival time of approximately one year. For patients with controlled systemic disease, good performance status, and a limited number of metastases, treatment typically entails surgical resection or radiosurgery, followed by whole brain radiotherapy (WBRT) to control microscopic disease. WBRT is known to control the progression of cancer in the brain, but it can also have toxic effects, particularly with regard to neurocognition. There is no consensus as to whether the benefit of WBRT outweighs the potential harm. We review the evidence related to the question of whether patients undergoing surgical resection of brain metastases should receive adjuvant WBRT.

Mcl-1 regulates the survival of adult neural precursor cells.

Since the discovery of neural precursor cells (NPCs) in the adult mammalian brain, there has been a lot of excitement surrounding the potential for regeneration in the adult brain. For instance, many studies have shown that a significant number of NPCs will migrate to a site of injury and differentiate into all of the neural lineages. However, one of the main challenges affecting endogenous neural regeneration is that many of the NPCs that migrate to the injury site ultimately undergo apoptosis. Therefore, we sought to determine whether myeloid cell leukemia-1 (Mcl-1), an anti-apoptotic Bcl-2 protein, would promote the survival of adult NPCs by impeding apoptosis. To do this, we first confirmed that Mcl-1 is endogenously expressed within the adult NPC population using BrdU labeling assays. Next, we conditionally deleted Mcl-1 in adult NPCs using cre/lox technology and expressed Cre from the NPC-specific promoter Nestin. In vitro, cells that had Mcl-1 conditionally deleted had a 2-fold increase in apoptosis when compared to controls. In vivo, we used electroporation to conditionally delete Mcl-1 in adult NPCs and assessed apoptosis at 72h. after electroporation. As in our in vitro results, there was a 2-fold increase in apoptosis when Mcl-1 was conditionally deleted. Finally, we found that Mcl-1 over-expression reduced the endogenous rate of adult NPC apoptosis 2-fold in vitro. Collectively, these results demonstrate that Mcl-1 is crucial for the survival of adult NPCs and may be a promising target for future neural regeneration therapies.

A validated LC-MS/MS assay for the simultaneous determination of the anti-leukemic agent dasatinib and two pharmacologically active metabolites in human plasma: application to a clinical pharmacokinetic study.

Dasatinib (Sprycel) is a potent antitumor agent prescribed for patients with chronic myeloid leukemia (CML). To enable reliable quantification of dasatinib and its pharmacologically active metabolites in human plasma during clinical testing, a sensitive and reliable liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated. Samples were prepared using solid phase extraction on Oasis HLB 96-well plates. Chromatographic separation was achieved isocratically on a Luna phenyl-hexyl analytical column. Analytes and the stable labeled internal standards were detected by positive ion electrospray tandem mass spectrometry. The assay was validated over a concentration range of 1.00-1000 ng/mL for dasatinib and its two active metabolites. Intra- and inter-assay precision values for replicate QC control samples were within 5.3% for all analytes during the assay validation. Mean QC control accuracy values were within ± 9.0% of nominal values for all analytes. Assay recoveries were high (>79%) and internal standard normalized matrix effects were minimal. The three analytes were stable in human plasma for at least 22 h at room temperature, for at least 123 days at -20°C, and following at least six freeze-thaw cycles. The validated method was successfully applied to the quantification of dasatinib and two active metabolites in a human pharmacokinetic study.

Quantitative interference by cysteine and N-acetylcysteine metabolites during the LC-MS/MS bioanalysis of a small molecule.

During LC-MS/MS quantification of a small molecule in human urine samples from a clinical study, an unexpected peak was observed to nearly co-elute with the analyte of interest in many study samples. Improved chromatographic resolution revealed the presence of at least 3 non-analyte peaks, which were identified as cysteine metabolites and N-acetyl (mercapturic acid) derivatives thereof. These metabolites produced artifact responses in the parent compound MRM channel due to decomposition in the ionization source of the mass spectrometer. Quantitative comparison of the analyte concentrations in study samples using the original chromatographic method and the improved chromatographic separation method demonstrated that the original method substantially over-estimated the analyte concentration in many cases. The substitution of electrospray ionization (ESI) for atmospheric pressure chemical ionization (APCI) nearly eliminated the source instability of these metabolites, which would have mitigated their interference in the quantification of the analyte, even without chromatographic separation. These results 1) demonstrate the potential for thiol metabolite interferences during the quantification of small molecules in pharmacokinetic samples, and 2) underscore the need to carefully evaluate LC-MS/MS methods for molecules that can undergo metabolism to thiol adducts to ensure that they are not susceptible to such interferences during quantification.

Uso de insecticidas: contexto y consecuencias ecológicas / Insecticide use: context and ecological consequences

Las restricciones de la sostenibilidad acerca del uso de insecticidas incluyen los efectos en la salud humana, los ecosistemas agrícolas (ejemplo, los insectos beneficiosos), el medio ambiente, en su sentido más amplio (por ejemplo, las especies que no son el objetivo, paisajes y comunidades) y la selección de los rasgos que confieren la resistencia a los insecticidas. Es posible encontrar ejemplos donde los insecticidas han tenido un impacto desastroso en todas aquellas variables y otros ejemplos donde los peligros que representaban han sido mitigados (por accidente o por diseño). En esta revisión examinamos lo que en la actualidad se puede concluir sobre el impacto de campo directo e indirecto y de largo plazo de los insecticidas en el medio ambiente. Proporcionamos ejemplos específicos, describimos los patrones actuales del uso de insecticidas, consideramos los contextos donde se usan los insecticidas y discutimos el papel de los reglamentos y leyes a fin de mitigar el riesgo. Discutimos cómo el uso de los insecticidas está cambiando como resultado de una mayor conciencia ambiental e inevitablemente, mientras discutimos las principales restricciones del uso de los insecticidas, también sugerimos por qué no se pueden descartar tan fácilmente.

Constraints to the sustainability of insecticide use include effects on human health, agroecosystems (e.g., beneficial insects), the wider environment (e.g., non-target species, landscapes and communities) and the selection of insecticide resistant traits. It is possible to find examples where insecticides have impacted disastrously on all these variables and others where the hazards posed have been (through accident or design) ameliorated. In this review, we examine what can currently be surmised about the direct and indirect long-term, field impacts of insecticides upon the environment. We detail specific examples, describe current insecticide use patterns, consider the contexts within which insecticide use occurs and discuss the role of regulation and legislation in reducing risk. We consider how insecticide use is changing in response to increasing environmental awareness and inevitably, as we discuss the main constraints to insecticide use, we suggest why they cannot easily be discarded.

Photorefractive keratectomy for treatment of flap complications in laser in situ keratomileusis.

PURPOSE: To present the results of photorefractive keratectomy (PRK) for treatment of laser in situ keratomileusis (LASIK) flap complications. METHODS: Compilation of case reports through solicitation on Kera-net, an Internet surgery discussion site. RESULTS: PRK was performed on 13 patients from 2 weeks to 6 months after LASIK flap complications. The technique used for the PRK varied. Epithelial removal was performed using no-touch phototherapeutic keratectomy (PTK) in six of the 13 patients and manual debridement in the other seven patients. A dilute solution of 20% ethanol was used to facilitate manual debridement in five of the seven patients. In two of these five patients, the epithelium was replaced as in laser-assisted subepithelial keratomileusis (LASEK). A solution of 0.02% mitomycin C was used after laser ablation to prevent haze formation in three patients. After an average 7 months of follow-up, uncorrected visual acuity was 20/20 in six patients, 20/25 in four patients, and 20/30 in two patients. The visual acuity in one patient was 20/80, purposely left undercorrected for monovision. Best spectacle-corrected visual acuity was 20/20 in 10 of 13 patients. Three patients were 20/25, losing one line of best spectacle-corrected visual acuity. On slit-lamp examination, at last follow-up appointment, stromal haze was graded from trace to none in all patients. CONCLUSIONS: Photorefractive keratectomy is a safe and effective technique for treatment of patients with LASIK flap complications.